An example to fetch an URL using Cloudflare workers

workers-fetch-example.js

addEventListener("fetch", event => {
  return event.respondWith(handleRequest())
})

async function handleRequest() {
  const init = {
  	"headers": {
		"x-rapidapi-key": "<replaceme>",
		"x-rapidapi-host": "community-open-weather-map.p.rapidapi.com"
	  },
  }
  const response = await fetch("https://community-open-weather-map.p.rapidapi.com/weather?q=London%2Cuk&lat=0&lon=0&callback=test&id=2172797&lang=null&units=%22metric%22%20or%20%22imperial%22&mode=xml%2C%20html", init)
  const results = await gatherResponse(response)
  return new Response(results, init)
}

/**
 * gatherResponse awaits and returns a response body as a string.
 * Use await gatherResponse(..) in an async function to get the response body
 * @param {Response} response
 */
async function gatherResponse(response) {
  const { headers } = response
  const contentType = headers.get("content-type") || ""
  if (contentType.includes("application/json")) {
    return JSON.stringify(await response.json())
  }
  else if (contentType.includes("application/text")) {
    return await response.text()
  }
  else if (contentType.includes("text/html")) {
    return await response.text()
  }
  else {
    return await response.text()
  }
}